Now that you've purchased the Optra K designed to provide you fast, reliable printing at an affordable price - look to Lexmark for the supplies designed in conjunction with your printer. The Print Unit, which came already installed in your Optra K has a long-life of 32,500 pages at 5% print coverage. But, when it comes time to replace it, the removal and installation is a piece of cake! This print unit ships with a 2.5K Toner Cartridge to get you started printing right away. Replacement cartridges for your print unit come in a single-pack or a dual pack. The Toner Cartridge has a 5,000 page yield, each, at 5% print coverage.